Synthetic polymeric materials are widely used nowadays to fabricate myriads of products, including medical devices. Many of such medical devices, due to its intrinsic surface hydrophobicity, e.g., inserters for intraocular lenses, interventional medical devices or contact lenses, require a hydrophilic and/or lubricious surface.
A number of methods have been developed for applying hydrophilic coatings on polymeric substrates in recent years. However, almost all of the methods involve in physical adsorption of the coating onto the polymeric substrate, or involve in a multiple-step-coating process which is costly and time consuming, or produce a coating that is too thick, especially for an IOL delivery device in that it can cause damage to the IOLs, or produce a coating that cannot withstand steam sterilization, or produce a coating that cannot be stored in a wet state, e.g., water or saline, for a period of years. As a result, there remains a need for a thin, durable and autoclavable hydrophilic and lubricious coating as well as simpler and less expensive coating processes.
Although most of the currently marketed contact lenses are hydrophilic to a large extent, many wearers still experience discomfort, particularly with those contact lenses using silicone as part of the base polymer. Various coating approaches have been made to hydrophilize silicone-based contact lenses but due to the characteristic of the silicone itself, all approaches had failed so far. As a result, there remains a need for improved methods for hydrophilizing contact lenses as well as simpler and less expensive coating processes.